• Title/Summary/Keyword: Signal Location

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Fair Queuing for Mobile Sink (FQMS) : Scheduling Scheme for Fair Data Collection in Wireless Sensor Networks with Mobile Sink (모바일 싱크를 위한 균등 큐잉(FQMS) : 모바일 싱크 기반 무선 센서 네트워크에서 균등한 데이터 수집을 위한 스케줄링 기법)

  • Jo, Young-Tae;Park, Chong-Myung;Lee, Joa-Hyoung;Seo, Dong-Mahn;Lim, Dong-Sun;Jung, In-Bum
    • Journal of KIISE:Information Networking
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    • v.37 no.3
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    • pp.204-216
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    • 2010
  • Since Sensor nodes around a fixed sink have huge concentrated network traffic, the battery consumption of them is increased extremely. Therefore the lifetime of sensor networks is limited because of huge battery consumption. To address this problem, a mobile sink has been studied for load distribution among sensor nodes. Since a mobile sink changes its location in sensor networks continuously, the mobile sink has time limits to communicate with each sensor node and unstable signal strength from each sensor node. Therefore, a fair and stable data collection method between a mobile sink and sensor nodes is necessary in this environment. When some sensor nodes are not able to send data to the mobile sink, a real-time application in sensor networks cannot be provided. In this paper, the new scheduling method, FQMS (Fair Queuing for Mobile Sink), is proposed for fair and stable data collection for mobile sinks in sensor networks. The FQMS guarantees balanced data collecting between sensor nodes for a mobile sink. In out experiments, the FQMS receives more packets from sensor nodes than legacy scheduling methods and provides fair data collection, because moving speed of a mobile sink, distance between a mobile sink and sensor nodes and the number of sensor nodes are considered.

Application of Terahertz Spectroscopy and Imaging in the Diagnosis of Prostate Cancer

  • Zhang, Ping;Zhong, Shuncong;Zhang, Junxi;Ding, Jian;Liu, Zhenxiang;Huang, Yi;Zhou, Ning;Nsengiyumva, Walter;Zhang, Tianfu
    • Current Optics and Photonics
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    • v.4 no.1
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    • pp.31-43
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    • 2020
  • The feasibility of the application of terahertz electromagnetic waves in the diagnosis of prostate cancer was examined. Four samples of incomplete cancerous prostatic paraffin-embedded tissues were examined using terahertz spectral imaging (TPI) system and the results obtained by comparing the absorption coefficient and refractive index of prostate tumor, normal prostate tissue and smooth muscle from one of the paraffin tissue masses examined were reported. Three hundred and sixty cases of absorption coefficients from one of the paraffin tissues examined were used as raw data to classify these three tissues using the Principal Component Analysis (PCA) and Least Squares Support Vector Machine (LS-SVM). An excellent classification with an accuracy of 92.22% in the prediction set was achieved. Using the distribution information of THz reflection signal intensity from sample surface and absorption coefficient of the sample, an attempt was made to use the TPI system to identify the boundaries of the different tissues involved (prostate tumors, normal and smooth muscles). The location of three identified regions in the terahertz images (frequency domain slice absorption coefficient imaging, 1.2 THz) were compared with those obtained from the histopathologic examination. The tissue tumor region had a distinctively visible color and could well be distinguished from other tissue regions in terahertz images. Results indicate that a THz spectroscopy imaging system can be efficiently used in conjunction with the proposed advanced computer-based mathematical analysis method to identify tumor regions in the paraffin tissue mass of prostate cancer.

Neutron Induced Capture Gamma Spectroscopy Sonde Design and Response Analysis Based on Monte Carlo Simulation (Monte Carlo 시물레이션에 기초한 포획모드 중성자-감마 스펙트럼 존데 설계 및 반응 분석)

  • Won, Byeongho;Hwang, Seho;Shin, Jehyun;Kim, Jongman;Kim, Ki-Seog;Park, Chang Je
    • Geophysics and Geophysical Exploration
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    • v.18 no.3
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    • pp.154-161
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    • 2015
  • For efficiently designing neutron induced gamma spectroscopy sonde, Monte Carlo simulation is employed to understand a dominant location of thermal neutron and classify the formation elements from the energy peak of capture gamma spectrum. A pulsed neutron generator emitting 14 MeV neutron particles was used as a source, and flux of thermal neutron was calculated from the twelve detectors arranged at each 10 cm intervals from the source. Design for reducing borehole effects using shielding materials was also applied to numerical sonde model. Moreover, principal elements and quantities of numerical earth models were verified through the energy spectrum analysis of capture gamma detected from a gamma detector. These results can help to enhance the signal-to-noise ratio, and determine an optimal placement of capture gamma detectors of neutron induced gamma spectroscopy sonde.

Analysis of Wireless Network in Freight Container Terminal and Methods for Service Quality Enhancement (컨테이너 터미널의 무선 네트워크 분석과 서비스 품질 향상 방안)

  • Han, Seung-Ho;Park, Hyun-Sung;Kim, Jong-Deok;Kim, Yong-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.3B
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    • pp.235-246
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    • 2009
  • The number of industry wireless networks based on IEEE 802.11 WLAN technology deployed in large outdoor work sites, such as freight container terminal, is increasing these days. Wider service coverage, frequent movements of stations and high requirement on service reliability are main characteristics of these networks compared to the conventional IEEE 802.11 networks used in home, office and school. While the importance of these networks Bets higher, we can hardly find previous studies including concrete analysis on these networks based on actual experiments. We carried out several field experiments at a freight container terminal to analyze its IEEE 802.11 network and found out some problematic situations, such as over 50% retransmission rates and frequent disruption of communication link while a station is moving. We explain why these problematic situations happen and suggest some solutions, such as application of mesh technology, smart handoff based on location and movement pattern and adjustment of signal strength and channel allocation. Methods and tools used in the experiments are also detailed in the paper which may be helpful for similar future studies.

QTL Analysis of Rice Heading-related Genes Using Cheongcheong/Nagdong Doubled Haploid Genetic Map (청청/낙동 배가반수체 유전자 지도를 이용한 쌀의 출수기 관련 양적형질유전자좌(QTL) 분석)

  • Jang, Yoon-Hee;Park, Jae-Ryoung;Kim, Kyung-Min
    • Journal of Life Science
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    • v.30 no.10
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    • pp.844-850
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    • 2020
  • Disaster-related extreme weather is rapidly increasing due to climate change. In Korea, typhoons accompanied by rainfall usually approach in August and September, causing great damage. The purpose of this study is to find a gene that regulates the heading date of rice in order to avoid loss of harvest from climate change and typhoons. Cheongcheong/Nagdong doubled haploid (CNDH) was used as the plant material to investigate the location of heading-related genes using QTL and sequence analysis by cloning the gene. In the distribution chart, the heading dates, culm lengths, panicle lengths, numbers of panicles, and 1,000-grain weights all have normal distributions. QTL analysis found 13 contigs on chromosome 8. One QTL, named qHd8, was detected on chromosome 8. The range at qHd8 was approximately 7.7 cM, with RM72 and RM404 markers near the peak. There were 13 contigs and 1 ORF. Protein sequence analysis showed that rice was similar to Os08g0341700, AtSFH13, and AtSFH7 proteins. Os08g0341700, which is involved in signal transduction, is similar to phosphatidylinositol transfer-like protein II, and complete information is not available, but it is believed to play a role in the phosphatidylinositol-specific signaling pathway related to Sec14P.

Characteristic MRI Findings of Spinal Metastases from Various Primary Cancers: Retrospective Study of Pathologically-Confirmed Cases (다양한 원발성 암의 척추전이 병변의 특징적인 자기공명영상 소견들: 병리학적으로 확인된 병변들의 후향적인 분석)

  • An, Chansik;Lee, Young Han;Kim, Sungjun;Cho, Hee Woo;Suh, Jin-Suck;Song, Ho-Taek
    • Investigative Magnetic Resonance Imaging
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    • v.17 no.1
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    • pp.8-18
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    • 2013
  • Purpose : The purpose of this study was to find and categorize the various magnetic resonance imaging (MRI) findings of spinal metastases that correlate with the type of primary cancer. Materials and Methods: We retrospectively reviewed gadolinium-enhanced magnetic resonance images of 30 patients with 169 spinal metastatic lesions from lung cancer (n = 56), breast cancer (n = 29), colorectal cancer (n = 20), hepatocellular carcinoma (HCC) (n = 17), and stomach cancer (n = 47). The size, location, extent of invasion, signal intensity, margin, enhancement pattern, and osteoblastic or osteolytic characteristics of each metastatic tumor were analyzed. Results: The metastatic lesions from HCC were larger than those from the other primary tumors (P < 0.05) except for colorectal cancer (P = 0.268). Well-defined metastatic tumor margins were more frequently seen in lung cancer and breast cancer (P < 0.01). All but HCC showed a tendency to invade the vertebral body rather than the posterior elements (P < 0.02). Colorectal cancer and HCC showed a tendency toward extraosseous invasion without statistical significance. HCC showed a characteristic enhancement pattern of 'worms-in-a-bag'. Rim enhancement with a sclerotic center was only seen in spinal metastases from stomach cancer. Conclusion: Despite many overlapping imaging features, spinal metastases of various primary tumors display some characteristic MRI findings that can help identify the primary cancer.

A Study on the Solutions of Guided Missile Attacks using 3-D RCS Data of Maritime Ship (함정의 3차원 RCS 측정 데이터를 활용한 유도탄 대응 기법 연구)

  • Gwak, Sang-Yell
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.4
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    • pp.552-557
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    • 2020
  • The Radar Cross Section (RCS) is a virtual region indicating the strength of a wavelength at which a radar signal is reflected and received. As the ship's RCS represents its own stealth performance and survivability, efforts have been made in various areas from design to construction to reduce the RCS. The RCS can be predicted using design drawings and CAD models, but it is necessary to measure the RCS at sea since sea clutter and multipath reflections occur in the sea environment. However, such RCS predictions and measured values provide only a simple relative magnitude to the user, and there has not been much research on this topic. In this paper, a missile countermeasure technique was studied using 3D RCS measurement data in an operating environment. The elevation and azimuth angle of the ship viewed from the missile were estimated using the location information of the missile, and the RCS value was inverted by mapping it to previously measured 3D RCS measurement data. In addition, by using the movement information of the missile, the RCS observed by the missile could be predicted in advance, and this method can be used to propose a response plan based on the maneuvering and chaff system.

Characterization of a New ${\beta}$-Lactamase Gene from Isolates of Vibrio spp. in Korea

  • Jun, Lyu-Jin;Kim, Jae-Hoon;Jin, Ji-Woong;Jeong, Hyun-Do
    • Journal of Microbiology and Biotechnology
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    • v.22 no.4
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    • pp.555-562
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    • 2012
  • PCR was performed to analyze the ${\beta}$-lactamase genes carried by ampicillin-resistant Vibrio spp. strains isolated from marine environments in Korea between 2006 and 2009. All 36 strains tested showed negative results in PCR with the primers designed from the nucleotide sequences of various known ${\beta}$-lactamase genes. This prompted us to screen new ${\beta}$-lactamase genes. A novel ${\beta}$-lactamase gene was cloned from Vibrio alginolyticus KV3 isolated from the aquaculture water of Geoje Island of Korea. The determined nucleotide sequence (VAK-3 ${\beta}$-lactamase) revealed an open reading frame (ORF) of 852 bp, encoding a protein of 283 amino acids (aa), which displayed low homology to any other ${\beta}$-lactamase genes reported in public databases. The deduced 283 aa sequence of VAK-3, consisting of a 19 aa signal peptide and a 264 aa mature protein, contained highly conserved peptide segments specific to class A ${\beta}$-lactamases including the specific amino acid residues STFK (62-65), SDN (122-124), E (158), and RTG (226-228). Results from PCR performed with primers specific to the VAK-3 ${\beta}$-lactamase gene identified 3 of the 36 isolated strains as V. alginolyticus, Vibrio cholerae, and Photobacterium damselae subsp. damselae, indicating the utilization of various ${\beta}$-lactamase genes including unidentified ones in ampicillin-resistant Vibrio spp. strains from the marine environment. In a mating experiment, none of the isolates transfered the VAK-3 ${\beta}$-lactamase gene to the Escherichia coli recipient. This lack of mobility, and the presence of a chromosomal acyl-CoA flanking sequence upstream of the VAK-3 ${\beta}$-lactamase gene, led to the assumption that the location of this new ${\beta}$-lactamase gene was in the chromosome, rather than the mobile plasmid. Antibiotic susceptibility of VAK-3 ${\beta}$-lactamase was indicated by elevated levels of resistance to penicillins, but not to cephalosporins in the wild type and E. coli harboring recombinant plasmid pKV-3, compared with those of the host strain alone. Phylogenetic analysis showed that VAK-3 ${\beta}$-lactamase is a new and separate member of class A ${\beta}$-lactamases.

Determination of Minimum Spacing between Off-ramp Terminus and Intersection Considering the Influence of Adjacent Signalized Intersections (신호교차로 영향에 따른 도시고속도로 유출연결로 최소이격거리에 관한 연구)

  • Kim, Sang-Gu;Sim, Dae-Yeong;Heo, Du-Wan
    • Journal of Korean Society of Transportation
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    • v.25 no.4
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    • pp.79-87
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    • 2007
  • The interchanges of urban freeways have many problems with traffic operation due to high off-ramp flows and frequent congestion at adjacent intersections. The flow exiting from off-ramps is affected by the operational status and traffic volume conditions of the nearest signalized intersection. As a result, off-ramp flow cannot exit and the queue backs up the freeway mainline when queues from the signalized intersection form up to the junction of the off-ramp and street. The spacing between an off-ramp and an adjacent intersection is likely to determine the traffic conditions at the adjacent intersection. However, the current design guidelines do not consider such a factor. This study is to develop a model calculating the spacing between off-ramps and adjacent intersections considering the signal, traffic, and road conditions. The variables affecting the model in this study are effective green time (g/C), volume-capacity ratio (v/c), the number of lanes, and off-ramp volume. Various scenarios are designed to represent the effects of the variables and the road networks are constructed using VISSIM, which is a common traffic micro-simulation software package. The queue length is derived from VISSIM and this length is considered as the recommended spacing between the off-ramp and the adjacent intersection. Through the simulation analysis, regression models are developed to calculate the queue length reflecting the various conditions such as signals, traffic, and road configurations. The developed model can be used to create road design guidelines to determine the location of off-ramps in the planning stage.

Study a Technique for Reducing the Influence of Scattered Rays from Surrounding Organs to the Heart during Gated Cardiac Blood Pool scan (Gated Cardiac Blood Pool scan에서의 심장 주위 배후방사능 관심영역 설정시 산란선의 영향을 감소시키기 위한 연구)

  • Kim, Jung-Yul;Park, Hoon-Hee;NamKoong, Hyuk;Cho, Suk-Won;Kim, Jae-Sam;Lee, Chang-Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.12 no.1
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    • pp.33-38
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    • 2008
  • Purpose: The Gated cardiac blood pool scan is non-invasive method that a quantitative evaluation of left ventricular function. Also this scan have shown the value of radionuclide ejection fraction measurements during the course of chemotherapy as a predictor of cardiac toxicity. Therefore a reliable method of monitoring its cardiotoxic effects is necessary. the purpose of this study is to minimize the overestimate of left ventricular ejection fraction (LVEF) by modified body position to reduce the influence of scattered rays from surrounding organs of the heart in the background region of interest. Materials and Methods: Gated cardiac blood pool scan using in vivo $^{99m}Tc$-red blood cell (RBC) was carried out in 20 patients (mean $44.8{\pm}8.6$ yr) with chemotherapy for a breast carcinoma. Data acquisition requires about 600 seconds and 24 frames of one heart cycle by the multigated acquisition mode, Synchronization deteriorates toward the end of the cycle and with the distance from the trigger signal (R-wave) by ECG gating. Gated cardiac blood pool scan was studied with conventional method (supine position and the detector head in $30-45^{\circ}$ left anterior oblique position and caudal $10-20^{\circ}$ tilt) and compared with modified method (left lateral flexion position with 360 mL of drinking water). LVEF analysis was performed by using the automatically computer mode. Results: The ROI counts of modified scan method were lower than LV conventional method ($1429{\pm}251$ versus $1853{\pm}243$, <0.01). And LVEF of modified method was also decrease compared with conventional method ($58.3{\pm}5.6%$ versus $65.3{\pm}6.1%$, <0.01). Imaging analysis indicated that stomach was expanded because of water and spleen position was changed to lateral inferior compared with conventional method. Conclusion: This study shows that the modified method in MUGA reduce the influence of scattered rays from surrounding organs. Because after change the body position to left lateral flexion and drinking water, the location of spleen, left lobe of liver and stomach had changed and they could escaped from background ROI. Therefore, modified method could help to minimize the overestimate LVEF (%).

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